All living individuals, i.e., plants and animals, are known to have complex systems for automatically maintaining their biological balances substantially independently of their central nervous system. Such systems are called "autonomic systems" and in warm blooded animals, for example, such systems are known to control such things as the body temperature, respiration rate and heart beat of the animal, for purposes which are fairly well understood. However, both plants and animals have been found to have autonomic systems controlling their electrodermal response for purposes which are not fully understood.
Furthermore, it has been found that the central nervous system of human beings can consciously and subconsciously control their autonomic systems including their electrodermal response. The conscious and subconscious control of respiration rate by the central nervous system is a common experience of all mankind. In recent years bio-feedback devices have enabled human experience of the conscious and subconscious control of such autonomic systems as heart beat, blood pressure, temperature, and electrodermal response, for example.
However, the conscious and subconscious control of such autonomic systems by the central nervous system as experienced in the prior art is often erratic, at best, particularly for electrodermal control. This is due, in part, to the fact that such autonomic systems are subject to simultaneous autonomic control which is by nature a primary effect, whereas the conscious and subconscious control of such autonomic systems by the central nervous system is a secondary effect. In other, words, although a human being may be able to consciously achieve an electrodermal response through the central nervous system, such response will tend to stimulate a counteracting autonomic response. Such autonomic response may be larger than the conscious response and may be followed by further autonomic responses directed toward restoring the original balance of the system. In addition, the individual may simultaneously exhibit an autonomic electrodermal response of many times such conscious response due to environmental effects such as the weather, temperature, atmospheric pressure, etc. Finally, a simultaneous subconscious electrodermal response through the central nervous system due to loud noises, personal psychological condition, etc., may occur which may either reinforce or counteract the conscious electrodermal response.
One object of this invention is to provide a reliable method and apparatus for utilizing "conscious" (i.e. "intentional" or "voluntary") electrodermal response and the like as a control means.